Continuous Fatty Acid Production: Comparative Technoeconomic and Life-Cycle Analysis between Subcritical Water and Lipase Methods

Abstract

Subcritical water hydrolysis and lipase-catalyzed hydrolysis (SWH and LPH, respectively) emerge as promising methods for hydrolyzing triglycerides to fatty acids. In this work, technoeconomic and environmental aspects of the two methods, using palm oil splitting as a model, at plant capacities of 10–200 tons/day have been investigated. While the annual operating costs of the two methods are comparable, SWH incurs significantly higher capital investment than LPH. As a result, the minimum selling price (MSP) of fatty acids for SWH is higher than that for LPH across all plant capacities studied. For the 10 tons/day capacity, the MSP values for SWH and LPH are 1.143 and 1.019 USD/kg, respectively. Heat integration is recommended so as to lower the MSP for SWH. Both alternative oil sources and longer lipase operational lifetime are important to the process economics. Finally, a cradle-to-gate life-cycle assessment clearly suggests that LPH is more environmentally friendly than SWH in all impact categories. The impacts of different life-cycle stages and use of sludge oils are also discussed.

Extraction of bioactive compounds from beach-cast brown algae: a review on accelerated solvent extraction and subcritical water extraction

“…While the study assumes equal phenolic extraction capacity (25 mg GAE per mg dry wt feedstock) across all methods for simplicity, it acknowledges that actual yields may vary in practice. Thakhiew et al 92 also performed a techno-economic analysis comparing SCW hydrolysis and lipase-catalyzed hydrolysis for continuous fatty acid production, using palm oil splitting as a model. Their results indicated that SCW hydrolysis (350 °C and 200 bar) requires higher capital investment and energy consumption than lipase-catalyzed hydrolysis, while the annual operating costs for both methods are comparable.…”

Low-Cost CO2-Based Alkyl Carbamate Ionic Liquids for Accelerating Enzymatic Oil Hydrolysis

“…The Colgate-Emery process, which is one of the well-known commercial hydrolysis processes, is conducted under operational temperatures from 250 to 340 °C, with a reaction pressure of 5 to 6 MPa and utilizes water at subcritical or supercritical states. , Despite the remarkable efficiency and conversion rate of 97% or higher, the elevated operational conditions induce increased vulnerability of triacylglycerols (TAGs) to undesired secondary reactions, including oxidation, dehydration, and the interesterification of generated fatty acids . The enzymatic approach involving lipases emerges as the preferred alternative for the conventional hydrolysis processes due to its operational conditions near ambient settings . Moreover, the enzymatic process also possesses the advantage of enhanced substrate specificity, thus mitigating undesired broad reactions and simplifying the overall synthesis and purification process. , …”

“…7 The enzymatic approach involving lipases emerges as the preferred alternative for the conventional hydrolysis processes due to its operational conditions near ambient settings. 8 Moreover, the enzymatic process also possesses the advantage of enhanced substrate specificity, thus mitigating undesired broad reactions and simplifying the overall synthesis and purification process. 9,10 Besides the transesterification of TAGs and esterification of free fatty acids (FFAs) to produce esters, there has been increasing interest among researchers in utilizing Eversa lipases for FFA production via oil hydrolysis.…”

Efficient Enzymatic Cascade Synthesis of α-Olefins via Colocalization onto Graphene Oxides and Liquid–Liquid Extraction

“…The traditional method for producing α-olefin is through the oligomerization of ethylene, , which could generate unwanted byproducts, leading to a low selectivity. , Moreover, ethylene is obtained from such petro-based, nonrenewable feedstocks such as crude oils. Recently developed approaches for α-olefins are metathesis and biorefinery. − Biorefinery allows for the utilization of biobased feedstocks such as fatty acids, which can be derived from triglycerides . Long-chain fatty acids can be converted to α-olefins via an enzymatic reaction.…”

“…8−10 Biorefinery allows for the utilization of biobased feedstocks such as fatty acids, which can be derived from triglycerides. 11 Long-chain fatty acids can be converted to α-olefins via an enzymatic reaction.…”